Internal-grinding machine



July15,1930.- I AR N 1,770,817

INTERNAL GRINDING MACHINE Filed Aug. 17, 1925 5 Sheets-Sheet 1 INVENTOR.

\ J TORNEYS.

July 15, 1930. A. P; STEINER 1,770,317

INTERNAL GRINDING mamas Filed Aug. 17, 1925 5 Sheets-Sheet 2 Juy 15, 1930. A. P. STEINER INTERNAL GRINDING momma 5 sheets-sheet 3 Filed Aug. 17, 1925 1 IN VENTOR. By #2720: Jtemen July 15,1930. A. E STEINER I ,8

INTERNAL GRINDING MACHINE Filed Aug. 1'7, 1925 5 Sheets-Sheet 4 m fi INVENTOR.

Amos Steiner I I BY rfimns.

y 930. A. P. STEINER 1,770,817

IMERNAL GRINDING MACHINE Filed Kug. 17, 1925 5 Sheets-Sheet 5 IN VEN TOR.

flmos Std/zen .ly in closing the circuit, thus eliminating the a tro nagnet therefor,

Patented July 15, 1939 i stares wast? OFFI Amos P. seamen-or WAYNESBOBO,QENNSYZVANIA, issienon r mums reonco M- PANY, or wavunsrzcno, rnnnsrnvama, A CORPOBATIONVTOF ,ZPENVNSYL'VANVIA INTEnNnL-emvmne MACHINE Application. filed August 17, 1925. Serial no. 50,779,

I dy saio invention relates to an automatic sizing devicetor internal rinding machines and it is an object or" the same to nrovide autonia-tic means whereby a grinding machine may be so controlledas to reduce hollow work to exactly the size desired, all without the at-' tention or assistance oi the operator.

Another object is to provide nieans whereby thework carriage is caused automatically to a travel away or be withdrawn from the wheel when the work has been ground to the desired size. r a y 7 Another object is to provide in a device of this character a circuit with a circuit breaker 5 having electrical contacts'which when open are widely separated, but which move very quickusual slow-moving contacts that burn and fuse the contact points and-so tend to make the device inaccurate.

Another obj ect is to provide meansw'hereby a work contacting linger is moved in radially from its feeling position as soon as the work is about to be withdrawn from the wheel.

3 Another object is to provide ineans whereby the work contacting finger is returned to the feeling position and the latch for the circuit breaker is returned to aciosed position after the wheel enters the workto 3 grind the newly inserted piece of work.

Another object is to provide means whereby a wheel dressing device is automatically thrown around into operating against the wheel while the work is in a withdressing operation to be performed automatically without loss of time as the work-holder carriage retreats and then advances to the operating position. i

Referring to the accompanying drawings, which are niade a part hereof and on which similar reference cliara ters indicate similar we a a Figurel is a front elevation of the sizing feeler mechanism withdrawal pawl and elec- Figure 2, when viewed from the right ofFigure 1,

Figure 3, arplan of the sizing feeler,

position drawn post-ion, thereby enabling the wheel Figure 4, a planview partly in section,v V

Figurefi, a side elevation of said device viewedfroin theright of Figure 3 or Figof the sizing feeler,

ure 4, V r Figure 6, an enlarged end view from the left showing the gr nding Wheel and the work contacting hn'ger in position in the work,

Figure 7, an enlarged front elevation of the I work contacting finger, and

F gure 8, an enlarged pla n view showing the wheel dresser and operating means thereof. 1 a

In the drawings (Figs. 1 and 2) reference character 10 indicates a bed or frame, "11 a a work. supporting carriage mounted to slide in guides 12, 10 an oscillating fluid inotor driving apinion 11 contacting with a rack 12' on the workcarriage 11 for moving the work carriage into and out of contact with the grinding w'heel,1 and '13 awheel carriage mounted in guides l t for reciprocation of the grinding wheel 15 for grinding short articles all of which parts are ormay be of the same design as is fully shown and described in my previous application for a fselective internal grinding machinwNo. 26,232, filed April 27, 1925.; The various features of this device are shown as appliedto amachine having the selective traverse features, but is will be' obvious that my improvements may be applied to any internal grinding machine having either the traversing worker the traversing wheel methods reciprocation, and it is my intention so to apply them.

i A supporting or bridge casting 16 is securely fastened at each end tothefrahie' 10 in such a Ina-Inner that thefwork carriage 11 may be free to pass under said bridge.

Manatee upon the bridge 16 is the base 17 of "tllQSlZlIig device said base beinginoiinted for adjustment lengthwise of the mach-inert e. crosswise of the bridge 16, comprising a slot 17 and a clamping screw 18 (Fig. 1 such adjustment providing means for locating the sizing device in accordance with the length ofthework. V a side elevation of said device {A- casing 19 i printed on the Base, said casing being adapted to slide upon the guides 2 0 towarder' away from the work to suit as riations in the diameter of the work. The pawl has been held to arrest the withdrawal casing is moved by means of an adyusting mechanism. The lower end 39' of the reversscrew 21 which has a 'raduated dial 22 upon which the movement of the casing may be read in thousandths. r

A work contacting finger 23 having adiamond point 24 for engaging the surface of the work 25 (Figs. 4, 5, 6, 7) is mounted for pivotal movement upon a vertical shaft 26,

said shaft being supported by two bearings 27 (Fig. which are in turn supported by the casing 19. Located on the shaft 26 between the two bearings is a forwardly extending arm 27 4), which is limited in its movement in one direction by the stop screw-28 and which holds the diamond 24 in engagement with the work by the action of a spring 29.

A hardened blockBO has a stem inserted in a hole in the free end of arm 27 and this block is shaped in section as a right-angled triangle,wvith a forward edge between 'a fiat face. and the inclined face defined by the hypotenuse of the triangle. The block 30 engages with its end face the adjacent face of a block 81 mounted on the circuit closer arm 32, the arm 27 holds the arm 32 inan inoperative position but as the finished size of the work is approached the said arm 27 is rotated by the spring 29. This movement is controlled by the feeler arm 23 inengagement with the work'25. The device has been set as described above so that when the work ias been ground to the desired size the arm 27 will have rotated "l ar enough to release the arm Preferably the tips of these faces are ground oil to provide smal-lflats which permits the parts to disengage suddenly and completely when the feelerfinger 23 has moved out far enough, i. e. when the work is finished. The arm is mounted on a shaft and supported by two bearings 34, which are in turn supported by the casing 19.

Mounted upon the arm 32 is a contact 35 adapted to engage contacts 35' to close a circuit indicated diagrammatically 1n Fwures '3 and 4. A spring 36 connected at opposite ends respectively to the arm 32 and tothe cas iug serves to move the contact 35 quickly into engagement with contacts 35. a The movement of the arm 27' is practically completed before the lever starts to move, the only remaining movement being over against the stop screw 28 and that can not be accomplished until after the circuit has been closed at 35, 35, and'the work has traversed away from the wheel so tar'that thediamond 24 is out of contact with the work, which then allows the arm 27 to move under the action or the spring 29 over against the screw 28.

An electromagnet 37 is energized upon the closing of the circui by the circuit closer 35 and said 'eleetromagnet lifts the pawlBS (Fig. 1) out of engagement with the, reversing lever 39, for the withdrawal movement, where the ing lever and abutment mechanism is of wellknown construction as, for example, in Landis 639,900, 820,801 and Stoner 1,533,047. The reversing lever 39 is operated by dogs upon the work carriage in almianner wellknown in the art and will not be further described herein. The patents to Landis above referred to are examples of such structure. Lifting ofthe pawl permits the withdrawal mechanism to become operative and withdraw the work 25 away from the grinding wheel 15'as for changing the work.

The shaft 26 has an arm 40 fixed thereto at its end said arm being provided with a roller for engagement with a cam 47 on a cam bar 42 at the front edge of the work carriage and the shaft has an arm 41 provided with a roller 44 for engagement with a cam 46 on a cam bar 43 similarly located. These cam bars participate in the withdrawal move ment, are pulled through in under the bridge by thismovement and are, of course, attached to the carriage 11 which supports the work holder.

A wheel dresserbase 48 is mounted for swiveling movement on the bridge 16 back of the grinding wheel 15. he wheel dresser base has a shaft 49 extending through the bridge 16 and an arm 50 bearing a roller 51 is secured to the lower end of said shaft. A bar or screw 52 is threaded in the upper end of the base 48 and a wheel dressing diamond 53 is mounted at one end of the bar in any con venient manner. 7 r

A spring 54 holds the device in a retracted position as shown in Fig. 8 when not in use. A canr55, acting against the'roller 51 when the work carriage 11 withdraws from the wheel, swings the wheel dressing device around into the position shown in dotted lines, so that the travel of the Wheel and the wheel carriage 13 will pass the wheel back and forth past the diamond, truing the wheel to proper condition for operation on the next piece of work.

In operation the work 25 being in operative position with the grinding wheel 15 grinding out the bore as shown in Fig. 4, the diamond 24'moves radially outward as the hon increases in sizethe arms 23 and 27 sw aging as tar aspermitted by the diamond a" the work is finished when the detent 30 allows the block 31 on: the switch arm 32 to pass closing the circuit by means of the contact and energizing theelectronagnet 37 which raises the pawl 38 and so permits the withdrawal mechanism'to pull 1 work away from the grinding wheel. It

weenie sin. see-seemed. that in aieepemaoa or the device, the movement olthe work carriage to the right as shown in Fig. 1 will'mov the reversing lever 39 to the position shown in Fig. 1 whereupon the lever 39 will he held in position'by the'meinbci' 38. At this time the abutment. 42 positioned beneath the roller 40 on the. lower end of the reversing lever,

will tend to urge t-h'e'reversing lever in a direction to reverse the carriage. however, is held 111 the pos tion shown in Fig. 1 at which. position thecarriage is inoperative. \Vhen pawl 38 has been raised the abutment l1 under the influence oi spring d2 will throw the lever 39*to a position to reverse the carria'geQ The finished work may now be removed and another piece inserted.

As the work carriage withdraws from the wheel .the cam 46 engages the roller id breaking the circuit of the electromagnet by r'e moving contact 35 from contacts 35and so allowing the pawl to drop down to operating position to engage the reversing lever for the withdrawal movement when thecarria'g'e returns.

The cam fl? then engages the roller returning the rockarms 10 and 23 and moving the diamond 24 out of contacting relation with the work 25, such movement being pernnttedby the relative s1zes of the stone I and the opening in the work (Fig. 6). This 7 movement of the diamond must be sufiicient to allow room for an unfinished piece of 5 work to be placed in operative position, the

unfinished piece, of course, having a smaller hole than the finished work.

The relation of the cams 46, 47 and their with the work 25 and hold it in retracted position until a new piece of work is in grinding position relatively to the wheel 15. This action also moves the arm 27 to the left of the position indicated in Figure 4 against 7 the tension of the spring 29 and brings the block 30 above the block 31.

On return to the grinding position the cam 4"? first permits the return of rockarms 40, 27 and 23 under the action of the spring 29 to a position determined by the internal diameter ot the work 25. hereafter the cam 46 perte sion of the spring 36 to a point/ determined hr the postion of the block 30. the block 31' against block 30 and thus prevent-1' ing engagementof the contacts of the circuit cl ,ser. r l 1 Upon completion of a piece of Work' the The lever,

miss the rockarms 41 and 32 to return under v worktztble 11, as hereinb'e'fore' explaine'ch inovestothe left carrying with it thefcams 4-6 and 47 whichare attached thereto. cam also travels with the worktable 11 at this time being also attached to the table and after the w'ork' has been disengaged from the wheel the cam 55 engages the roller 51 thereby swinging the rockarrns 50 "and" 48 from the solid line position in Fig.3 to the dotted line p'ositionfagainst the tension of spring 5 1 This brings the wheeldressing device nto the position ind catedfm dotted lines with the diamond 53 into position to contact with the wheel; In the machine here illustrated the wheel has a constant traversing movement and the travel ofthe work carator to remove the finishedwork and insert a new piece of work or such travel can be stopped at theend ofthe outward stroke at the option of the operator. This travel of the work. carriage will also be sufficient in The riage into work replenishing position and back maybe so regulated as to allow the'open.

ordinary cases to permit the wheel dressing operation to be completed by the time the work carriage-returns with anew piece of work.

' The various details oi -time relation, etc; will of course be arranged in accordance with the nature of the particular grinding machine. i v Q The unfinishedpiece of'work'having been positioned the work" approaches the wheel and the wheel enters the work. As this takes place all three cams, 55', 47 and 46, move to the right as seen in Figures land 8, the cam 55 returns to the position indicated in Figure 8 aiid'thespring 54 returns the work dresser to the position indicated in full lines. T here"- upon thewhel enters the work ancl the cam 47 permits the" diamond 24 to engage the work after which the cam 46 allowsthe block 2 31 to latch up against the block 30'. After the grinding I wheel has removed sufficierit material to bring thework to predetermined size the block 30 moves back e'nough'to allow ltrl'ock 31 to pass closingthe contact at 35 and repeating the entire withdrawal operation. The work may be fed toward the wheel during thefgrinding operation or the'wheel they be fed toward the work and this'is done by conventional means well known to those skilled in the are n Order to ea this device to aming as .ofa given diameter, a piece which has already been ground to {exact slze and checked by a micrometer, is placed'in a chuck. The arm 2.3

,is insert ed in the week-enumerated24,111

mama; witht-he finishedsurface'whil'the housing 19 is in a withdrawn position, that is, toward the operator; saidhousing is then moved toward the work by means of a knob 21. Asthisniovemeiit progressedthe spring i'kepjs the diamond 24inc ontact with the w" i125 so that t-lie arms 2 3and 27 armor-area 1n a" counter-clockwise err-action. The housing is moved until the arm 27 has rotated far enough to release the arm 32. At this point on the graduated dial 22 is a proper setting for the given diameter. 7

It will be obvious to those skilled in the art that various changes may be made in my device without departing from the spirit of the invention and therefore I do not limit myself toawhat is shown in the drawings and described in the specification but only as indicated in the appended claims.

Having thus fully described my said invention, what I claim as new and desire to secure by Letters Patent, is:

1. In agrinding machine, a work holding device, anvabrading device, a carriage for one of said devices'movable toward or from abrading proximity to the'other means for moving said carriage, a feeler engaging the work, electrically operated means for controlling the withdrawal 'of the carriage, a pivoted circuit-closer biasedtoclose an electric circuit for said last-named means, a trip for holding said circuit closer in open position, connections between the feeler and the trip for releasing said circuit closer, a cam movable by the carriage withdrawal movement for returning the circuit-closer to open position, and a cam moved by the carriage for thereafter resetting the trip, substantially as set forth.

2. In a grinding machine a work holding device, an abrading device, a carriage for moving one of said devices to a non-abrading distance means for moving. said carriage, a

feeler adapted to be positioned within the work in engagement therewith, electrically operated means for controlling the withdrawal of the carriage to the remote position, a pivoted circuit-closer biased to close the electric circuit, a, trip for holding said circuitcloser inopen position, connections between the feeler and the trip for releasing said circuit-closer, means attached to the carriage for returning the circuit-closerto open position, and means attached to thecarriage for thereafter resetting the trip, substantially as set forth.

8. In an internal grindingmachine, abrading means, work holdingvmeans, means to move the workholding means with respect to the abradmg means, and means for controlling said work moving means comprising a housing, a normally open electric circuit in said housing, an arm adapted to close said circuit, a second arm mounted in said housing and tending normally to prevent closing of said electric circuit, a third arm adapted v to contact with a Work piece and also to co operate with said second arm, means to move said second arm to release said first arm, and means whereby said th1rd arm controls the movement in the secondarm so as to release the first arm when the desired size has been attained, and means operable by movement of the work holding means for moving said third arm to position its work contacting end within the work as the work holding means moves to abrading position, substantially as set forth. I

4. In an internal grinding machine, a work holding device, an abrading device, a carriage for one of said devices movable toward or from abrading proximity to the other, a driving mechanism for said carraige, a normally operative reversing lever for said mechanism, a pawl adapted to stop said lever in inoperative position, resilient means urging the lever to operative position, electricallyv operated means for controlling the withdrawal of the carriage comprising an electro-magnet operable toliftsaid pawl to allow the lever to move to operative position, a circuit closer, a trip to hold said circuit closer in open position, a feeler engaging the work, connections between thefeeler and the trip for releasing saidcircuit closer,cams on the carriage operable on the withdrawal of the carriage to return the circuit closer to open position, and means whereby said cams reset the trip as the carriage moves toward the work, substantial ly as set forth. 7

In witness whereof I have hereunto set my hand at Vaynesboro, Pennsylvania this twelfth day of August, A. D. nineteen hundred and twenty-five.

AMOS P. STEINER. 

